Reptiles

Question 1

What are reptiles derived from?

Answer 1

A group of labyrinthodont amphibians known as anthracosaurs

Question 2

Reptiles are a ________ group that gave rise to mammals and birds.

Answer 2

Paraphyletic

Question 3

Together, mammals, reptiles and birds constitute a monophyletic group called ________.

Answer 3

Amniota

Question 4

Name the four extant forms of reptiles

Answer 4

Crocodilians (crocodiles, gharials, caiman and alligators) DIAPSIDA

Sphenodontia (tuataras) DIAPSIDA

Squamata (lizards, snakes and amphibaenids) DIAPSIDA

Testudines (turtles and tortoises) ANAPSIDA

Question 5

What does the cleidoic egg do?

Answer 5

1) acts as a self-contained environment for development
2) allows animals to bypass larval hatch as miniature adults
3) Shell and extra-embryonic membranes to prevent drying
4) Supply nutrients, water and oxygen
5) remove/store waste products
6) Terrestrial development of embryo without desiccation

Question 6

Name the four extra-embryonic membranes in the cleidoic egg.

Answer 6

Allantois
Chorion
Amnion
Yolk sac

Question 7

What does the amnion membrane do?

Answer 7

It encloses the embryo in a fluid-filled sac for protection

Question 8

What does the chorion do?

Answer 8

It lines the egg shell and provides protection and allows for gas exchange

Question 9

What does the allantois do?

Answer 9

Also important for gas exchange and provides a sac where nitrogenous waste is stored away from the embryo

Question 10

What does the yolk sac do?

Answer 10

Contains yolk/nutrients as food for the developing embryo

Question 11

What terms are used to describe egg layers and live-bearers?

Answer 11

1) Oviparity = egg layers

2) Viviparity = live-bearers

Question 12

Reptilian skin is dry and scaly and minimises ______________.

Answer 12

Water loss

Question 13

Name four ways in which a reptile tries to maintain body temperature.

Answer 13

1) Orientation
2) Contours
3) Colour
4) Blood flow

Question 14

Name three advantages of being an ectotherm

Answer 14

1) Expend less energy
2) Requires less food
3) Fewer energetic constraints on body size

Question 15

Name three disadvantages of being an ectotherm

Answer 15

1) They are less active in cooler temperatures and have to warm up in the sun which puts them at risk of predators
2) They are unable to increase respiration rates to increase internal heat
3) Biological functions constrained

Question 16

Why can many reptiles not sustain running?

Answer 16

The muscles used for respiration are the same ones used for running, so during running respiration is impaired.

Question 17

Amphibians have ______ occipital _______ and ______ cervical vertebra

Answer 17

Two occipital condyles and one cervical vertebra

Question 18

Reptiles have _________ _________ condyles and __________ cervical vertebrae

Answer 18

One occipital condyle and two or more cervical vertebrae

Question 19

What do the changes in the number of occipital condyles and cervical vertebrae between amphibians to reptiles increase?

Answer 19

Head mobility.

Question 20

Describe amphibian skulls.

Answer 20

Flat and broad.

Question 21

Describe reptile skulls.

Answer 21

Deep and narrow.

Question 22

What do amphibians have that allows them to close their jaw rapidly and what type of jaw is this called?

Answer 22

They have a pair of vertically orientated muscles that close the jaw rapidly. This jaw is called a snap-trap jaw and allows them to swallow food whole with little or no food processing.

Question 23

________________ process is absent in amphibians except for in ___________ _____________

Answer 23

Pterygoid process is absent in amphibians except for in advanced anthracosaurs.

Question 24

The pterygoid process is present in reptiles and is a synapomorphy for _________ and ___________

Answer 24

Advanced anthracosaurs and amniotes.

Question 25

The pterygoid process is associated with what?

Answer 25

The bifurcation of a single amphibian muscle into two muscles, the adductor mandibulae and the pterygoideus.

Question 26

When does the adductor mandibulae exert its strongest force?

Answer 26

When the jaws are closed. It helps crush food and provides for increased food processing capabilities.

Question 27

What is the term used to describe mobility within the head skeleton?

Answer 27

cranial kinesis

Question 28

Snakes have lost their mandibular _________.

Answer 28

Mandibular symphysis

Question 29

What is the mandibular symphysis?

Answer 29

A bony articulation joining the two halves of the mandible.

Question 30

What feature allows the mandible to flex in snakes?

Answer 30

The intramandibular hinge

Question 31

What are snakes closest living relatives?

Answer 31

Anguimorph and iguanian lizards.

Question 32

Vision is usually adapted for ________ conditions, with _______ vision and more advanced __________ than in amphibians.

Answer 32

Vision is usually adapted to DAYLIGHT conditions, with COLOUR vision and more advanced DEPTH PERCEPTION than in amphibians.

Question 33

The simplified snake eye suggests what?

Answer 33

Re-evolution of the eye